JP6717372B2 - Charge transport varnish - Google Patents

Description

The present invention relates to a charge transporting varnish.

In an organic electroluminescence (hereinafter referred to as organic EL) element, a charge transporting thin film made of an organic compound is used as a light emitting layer and a charge injection layer. In particular, the hole injecting layer plays a role of transferring charges between the anode and the hole transporting layer or the light emitting layer, and plays an important function for achieving low voltage driving and high brightness of the organic EL element.
The method for forming the hole injection layer is roughly classified into a dry process typified by a vapor deposition method and a wet process typified by a spin coating method. Comparing each of these processes, the wet process is flat in a large area. A highly efficient thin film can be efficiently manufactured. Therefore, as the area of an organic EL display is being increased, a hole injection layer that can be formed by a wet process is desired.
In view of such circumstances, the inventors of the present invention are applicable to various wet processes, and when applied to a hole injection layer of an organic EL device, the present invention provides a thin film capable of realizing excellent EL device characteristics. Materials and compounds with good solubility in organic solvents used for them have been developed (see, for example, Patent Documents 1 to 5).
However, there is a constant demand for improvements in wet process materials for hole injection layers, and in particular, there is a demand for wet process materials that provide thin films with excellent charge transport properties.

International Publication No. 2008/032616 International Publication No. 2008/129947 International Publication No. 2006/025342 International Publication No. 2010/058777 JP, 2014-205624, A

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a charge-transporting varnish that gives a charge-transporting thin film excellent in charge-transporting property, flatness, and uniformity with good reproducibility.

The present inventors have conducted extensive studies to achieve the above object, and as a result, from a varnish obtained by dissolving a charge-transporting substance and a predetermined onium borate salt in an organic solvent, the charge-transporting property and the flatness are obtained. It was found that a charge transporting thin film excellent in uniformity and uniformity can be obtained with good reproducibility, and that an organic EL device having excellent brightness characteristics can be obtained by using the thin film as a hole injection layer, and the present invention has been completed. It was

（式中、Ｒは、炭素数１〜１０のアルキル基、炭素数１〜１０のフルオロアルキル基、炭素数７〜１０のアラルキル基または炭素数７〜１０のフルオロアラルキル基を表す。）
２． 前記電荷輸送性物質が、アニリン誘導体およびチオフェン誘導体から選ばれる少なくとも１種である１の電荷輸送性ワニス、
３． 前記電荷輸送性物質が、アニリン誘導体である２の電荷輸送性ワニス、
４． １〜３のいずれかの電荷輸送性ワニスを用いて作製される電荷輸送性薄膜、
５． ４の電荷輸送性薄膜を有する有機エレクトロルミネッセンス素子、
６． １〜３のいずれかの電荷輸送性ワニスを基材上に塗布し、溶媒を蒸発させることを特徴とする電荷輸送性薄膜の製造方法
を提供する。That is, the present invention is
1. A charge transporting material comprising a charge transporting substance, an onium borate salt, and an organic solvent, wherein the onium borate salt comprises an onium borate salt consisting of an anion represented by formula (a1) and a counter cation. varnish,

(In the formula, R represents an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or a fluoroaralkyl group having 7 to 10 carbon atoms.)
2. 1. The charge-transporting varnish, wherein the charge-transporting substance is at least one selected from aniline derivatives and thiophene derivatives,
3. 2. The charge-transporting varnish according to 2, wherein the charge-transporting substance is an aniline derivative,
4. A charge-transporting thin film produced by using the charge-transporting varnish according to any one of 1 to 3,
5. An organic electroluminescent device having a charge transporting thin film of 4;
6. Provided is a method for producing a charge-transporting thin film, which comprises applying the charge-transporting varnish of any one of 1 to 3 onto a substrate and evaporating the solvent.

By using the charge-transporting varnish of the present invention, a charge-transporting thin film having excellent charge-transporting property, flatness and uniformity can be obtained.
Further, the charge transporting thin film having such characteristics can be suitably used as a thin film for electronic devices including organic EL elements. In particular, by applying this thin film to the hole injection layer of an organic EL element, an organic EL element with a low driving voltage can be obtained.
Furthermore, the charge-transporting varnish of the present invention can produce a thin film excellent in charge-transporting property with good reproducibility even when using various wet processes capable of forming a film on a large area, such as a spin coating method and a slit coating method. It can sufficiently cope with the recent progress in the field of organic EL devices.
Since the thin film obtained from the charge-transporting varnish of the present invention is excellent in charge-transporting property, it can be expected to be used as an anode buffer layer, an antistatic film or the like of an organic thin-film solar cell.

Hereinafter, the present invention will be described in more detail.
The charge-transporting varnish according to the present invention contains a charge-transporting substance, an onium borate salt, and an organic solvent, and the onium borate salt is an onium borate salt comprising an anion represented by the formula (a1) and a counter cation. It includes.
Note that the charge-transporting property has the same meaning as the conductivity and the hole-transporting property. Further, the charge-transporting varnish of the present invention may have charge-transporting properties by itself, or the solid film obtained by using the varnish may have charge-transporting properties.

In formula (a1), R represents an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or a fluoroaralkyl group having 7 to 10 carbon atoms.
The alkyl group having 1 to 10 carbon atoms may be linear, branched, or cyclic, and examples thereof include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and s. -Butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and the like straight or branched having 1 to 10 carbon atoms. Chain alkyl group; cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, cyclononyl group, cyclodecyl group, bicyclobutyl group, bicyclopentyl group, bicyclohexyl group, bicycloheptyl group, bicyclooctyl group Examples thereof include a cyclic alkyl group having 3 to 10 carbon atoms such as a group, a bicyclononyl group, and a bicyclodecyl group, but an alkyl group having 1 to 8 carbon atoms is preferable, and an alkyl group having 1 to 6 carbon atoms is more preferable.

Examples of the aralkyl group having 7 to 10 carbon atoms include groups in which at least one hydrogen atom of an alkyl group is substituted with an aryl group, and examples thereof include a benzyl group, a 1-naphthylmethylene group, a 2-naphthylmethylene group, and phenylethylene. Group, a 1-naphthylethylene group, a 2-naphthylmethylene group, and the like, but an aralkyl group having 7 to 9 carbon atoms is preferable.

Specific examples of the fluoroalkyl group having 1 to 10 carbon atoms include groups in which at least one hydrogen atom of the alkyl group having 1 to 10 carbon atoms is substituted with a fluorine atom.
Specific examples thereof include fluoromethyl group, difluoromethyl group, trifluoromethyl group, pentafluoroethyl group, 2,2,2-trifluoroethyl group, heptafluoropropyl group, 2,2,3,3,3- Pentafluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2,2,2-trifluoro-1-(trifluoromethyl)ethyl group, nonafluorobutyl group, 4,4,4-trifluoro group Butyl group, undecafluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, 2,2,3,3,4,5,5-octafluoro group Pentyl group, tridecafluorohexyl group, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl group, 2,2,3,3,4,4,4 5,5,6,6-decafluorohexyl group, 3,3,4,4,5,5,6,6,6-nonafluorohexyl group and the like can be mentioned.

Specific examples of the fluoroaralkyl group having 7 to 10 carbon atoms include groups in which at least one hydrogen atom of the aralkyl group having 7 to 10 carbon atoms is substituted with a fluorine atom.
Specific examples thereof include a perfluorobenzyl group, a pentafluorophenylmethylene group, a heptafluoro-1-naphthylmethylene group, a heptafluoro-2-naphthylmethylene group, a heptafluoro-1-naphthylethylene group, and a heptafluoro-2-naphthyl group. Examples thereof include ethylene group.

Examples of the alkylaryl borate that can be preferably used in the present invention include those represented by the following formulas, but the present invention is not limited thereto.

On the other hand, the counter cation is not particularly limited, but a cation represented by the formula (c1) is preferable.

E in the formula (c1) represents an element having a valence of n of group 15 to 17, and therefore n represents an integer of 1 to 3 corresponding to the valence of E.
In the above R', n+1 units are bonded to E, and they independently represent a monovalent organic group, but two or more R's are mutually directly or —O—, —S—, —SO. _{-, - SO 2 -, -} NH -, - CO -, - COO -, - CONH-, may form a ring structure together with the element E is attached via an alkylene group or a phenylene group.
The monovalent organic group is not particularly limited, but is substituted with an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, or Z. Optionally, an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 14 carbon atoms, which may be substituted with Z.

The alkyl group having 1 to 20 carbon atoms may be linear, branched or cyclic, and may be, for example, n-undecyl group or n-, in addition to the groups exemplified as the alkyl group having 1 to 10 carbon atoms. Dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosanyl group and the like, but the number of carbon atoms An alkyl group having 1 to 18 is preferable, and an alkyl group having 1 to 8 carbons is more preferable.

Specific examples of the alkenyl group having 2 to 20 carbon atoms include ethenyl group, n-1-propenyl group, n-2-propenyl group, 1-methylethenyl group, n-1-butenyl group, n-2-butenyl group, n-3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, n- Examples thereof include a 1-pentenyl group, an n-1-decenyl group, an n-1-eicosenyl group and the like.
Specific examples of the alkynyl group having 2 to 20 carbon atoms include ethynyl group, n-1-propynyl group, n-2-propynyl group, n-1-butynyl group, n-2-butynyl group and n-3-butynyl group. Group, 1-methyl-2-propynyl group, n-1-pentynyl group, n-2-pentynyl group, n-3-pentynyl group, n-4-pentynyl group, 1-methyl-n-butynyl group, 2- Methyl-n-butynyl group, 3-methyl-n-butynyl group, 1,1-dimethyl-n-propynyl group, n-1-hexynyl group, n-1-decynyl group, n-1-pentadecynyl group, n- Examples thereof include a 1-eicosynyl group.

Specific examples of the aryl group having 6 to 20 carbon atoms include phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group and 2-phenanthryl group. Group, 3-phenanthryl group, 4-phenanthryl group, 9-phenanthryl group and the like, but an aryl group having 6 to 14 carbon atoms is preferable.

Z is an alkyl group having 1 to 20 carbon atoms, a haloalkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and a carbon number. 2-20 heteroaryl group, nitro group, hydroxyl group, cyano group, C1-8 alkoxy group, C6-20 aryloxy group, C1-20 acyl group, C1-20 It represents an acyloxy group, an alkylthio group having 1 to 8 carbon atoms, an arylthio group having 6 to 20 carbon atoms, an alkylamino group having 1 to 8 carbon atoms, an arylamino group having 6 to 20 carbon atoms, an amino group or a halogen atom.
Examples of the alkyl group, alkenyl group, alkynyl group and aryl group include the same ones as described above.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom is preferable.

Specific examples of the heteroaryl group having 2 to 20 carbon atoms include 2-thienyl group, 3-thienyl group, 2-furanyl group, 3-furanyl group, 2-oxazolyl group, 4-oxazolyl group, 5-oxazolyl group, Oxygen-containing heteroaryl groups such as 3-isoxazolyl group, 4-isoxazolyl group, 5-isoxazolyl group, 2-thiazolyl group, 4-thiazolyl group, 5-thiazolyl group, 3-isothiazolyl group, 4-isothiazolyl group, 5-isothiazolyl group Groups such as sulfur-containing heteroaryl groups, 2-imidazolyl groups, 4-imidazolyl groups, 2-pyridyl groups, 3-pyridyl groups, 4-pyridyl groups, 2-pyrazyl groups, 3-pyrazyl groups, 5-pyrazyl groups, 6 -Pyrazyl group, 2-pyrimidyl group, 4-pyrimidyl group, 5-pyrimidyl group, 6-pyrimidyl group, 3-pyridazyl group, 4-pyridazyl group, 5-pyridazyl group, 6-pyridazyl group, 1,2,3- Triazin-4-yl group, 1,2,3-triazin-5-yl group, 1,2,4-triazin-3-yl group, 1,2,4-triazin-5-yl group, 1,2, 4-triazin-6-yl group, 1,3,5-triazin-2-yl group, 1,2,4,5-tetrazin-3-yl group, 1,2,3,4-tetrazin-5-yl Group, 2-quinolinyl group, 3-quinolinyl group, 4-quinolinyl group, 5-quinolinyl group, 6-quinolinyl group, 7-quinolinyl group, 8-quinolinyl group, 1-isoquinolinyl group, 3-isoquinolinyl group, 4-isoquinolinyl group Group, 5-isoquinolinyl group, 6-isoquinolinyl group, 7-isoquinolinyl group, 8-isoquinolinyl group, 2-quinoxanyl group, 5-quinoxanyl group, 6-quinoxanyl group, 2-quinazolinyl group, 4-quinazolinyl group, 5-quinazolinyl group Group, 6-quinazolinyl group, 7-quinazolinyl group, 8-quinazolinyl group, 3-cinnolinyl group, 4-cinnolinyl group, 5-cinnolinyl group, 6-cinnolinyl group, 7-cinnolinyl group, 8-cinnolinyl group, etc. Heteroaryl groups and the like can be mentioned.

Specific examples of the haloalkyl group having 1 to 8 carbon atoms include a group obtained by substituting at least one hydrogen atom of the alkyl group having 1 to 8 carbon atoms with a halogen atom among the alkyl groups exemplified above. The halogen atom may be any of chlorine, bromine, iodine and fluorine atom. Among them, a fluoroalkyl group is preferable, and a perfluoroalkyl group is more preferable.
Specific examples of the fluoroalkyl group include those similar to the above.

Specific examples of the alkoxy group having 1 to 8 carbon atoms include methoxy group, ethoxy group, n-propoxy group, i-propoxy group, c-propoxy group, n-butoxy group, i-butoxy group, s-butoxy group, Examples thereof include t-butoxy group, n-pentoxy group, n-hexoxy group, n-heptyloxy group and n-octyloxy group.
Specific examples of the aryloxy group having 6 to 20 carbon atoms include phenoxy group, 1-naphthyloxy group, 2-naphthyloxy group, 1-anthryloxy group, 2-anthryloxy group, 9-anthryloxy group. , 1-phenanthryloxy group, 2-phenanthryloxy group, 3-phenanthryloxy group, 4-phenanthryloxy group, 9-phenanthryloxy group and the like.

Specific examples of the acyl group having 1 to 20 carbon atoms include formyl group, acetyl group, propionyl group, butyryl group, isobutyryl group, valeryl group, isovaleryl group and benzoyl group.
Specific examples of the acyloxy group having 1 to 20 carbon atoms include formyloxy group, acetoxy group, propionyloxy group, butyryloxy group, isobutyryloxy group, valeryloxy group, isovaleryloxy group and benzoyloxy group. ..

Specific examples of the alkylthio group having 1 to 8 carbon atoms include methylthio group, ethylthio group, n-propylthio group, isopropylthio group, n-butylthio group, isobutylthio group, s-butylthio group, t-butylthio group, n- Examples include a pentylthio group, an n-hexylthio group, an n-heptylthio group, an n-octylthio group and the like.
Specific examples of the arylthio group having 6 to 20 carbon atoms include phenylthio group, 1-naphthylthio group, 2-naphthylthio group, 1-anthrylthio group, 2-anthrylthio group, 9-anthrylthio group, 1-phenanthrylthio group, 2 -Phenanthrylthio group, 3-phenanthrylthio group, 4-phenanthrylthio group, 9-phenanthrylthio group and the like.

Specific examples of the alkylamino group having 1 to 8 carbon atoms include a dimethylamino group, a diethylamino group, a di-n-propylamino group, a di-i-propylamino group, a di-n-butylamino group, a di-i-butylamino group, Examples thereof include a di-n-pentylamino group, a di-n-hexylamino group, a di-n-heptylamino group, a di-n-octylamino group and a methylethylamino group.
Specific examples of the C6-20 arylamino group include diphenylamino group, 1-naphthylphenylamino group, di(1-naphthyl)amino group, 1-naphthyl-2-naphthylamino group, di(2-naphthyl). ) Examples include amino groups.

Among the elements of Groups 15 to 17, O is preferably O (oxygen), N (nitrogen), P (phosphorus), S (sulfur) or I (iodine) as the above E, and particularly stable and easy to handle. More preferred are S, I, N, and P, which give various onium ions, and even more preferred are S and I. Corresponding onium ions are oxonium, ammonium, phosphonium, sulfonium, iodonium.

Specific examples of the onium ion represented by the above (R′) _n+1 −E ⁺ include, but are not limited to, the following.
Specific examples of the oxonium ion include oxonium such as trimethyloxonium, diethylmethyloxonium, triethyloxonium, and tetramethylenemethyloxonium; 4-methylpyrrinium, 2,4,6-trimethylpyrrinium, 2,6 Examples thereof include pyrinium such as -di-t-butylpyrrinium and 2,6-diphenylpyrrinium; and chromium and isochromen such as 2,4-dimethylchromenium and 1,3-dimethylisochromenium.

Specific examples of the ammonium ion include tetraalkylammonium such as tetramethylammonium, ethyltrimethylammonium, diethyldimethylammonium, triethylmethylammonium and tetraethylammonium; N,N-dimethylpyrrolidinium, N-ethyl-N-methylpyrrolidinide. Pyrrolidinium such as N, N,N-diethylpyrrolidinium; N,N'-dimethylimidazolinium, N,N'-diethylimidazolinium, N-ethyl-N'-methylimidazolinium, 1,3,3 Imidazolinium such as 4-trimethylimidazolinium and 1,2,3,4-tetramethylimidazolinium; Tetrahydropyrimidinium such as N,N'-dimethyltetrahydropyrimidinium; N,N'-Dimethylmol Morpholinium such as folinium; Piperidinium such as N,N′-diethylpiperidinium; Pyridinium such as N-methylpyridinium, N-benzylpyridinium and N-phenacylpyridinium; Imidazo such as N,N′-dimethylimidazolium Lithium; quinolium such as N-methylquinolium, N-benzylquinolium and N-phenacylquinolium; isoquinolium such as N-methylisoquinolium; Examples thereof include acridium such as benzyl acridium and phenacyl acridium.

Specific examples of the phosphonium ion include tetraphenylphosphonium, tetra-p-tolylphosphonium, tetrakis(2-methoxyphenyl)phosphonium, tetrakis(3-methoxyphenyl)phosphonium, tetrakis(4-methoxyphenyl)phosphonium, and the like. Triarylphosphonium such as triphenylbenzylphosphonium, triphenylphenacylphosphonium, triphenylmethylphosphonium, triphenylbutylphosphonium; triethylbenzylphosphonium, tributylbenzylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, tetrahexylphosphonium, triethylphenacylphosphonium And tetraalkylphosphonium such as tributylphenacylphosphonium.

Specific examples of the sulfonium ion include triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4 -Fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, 4-(phenylthio)phenyldiphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolyl Sulfonium, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium , 4-(phenylthio)phenyldi-p-tolylsulfonium, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenylsulfonium, [4-(2-thioxanthonylthio)phenyl]diphenylsulfonium, bis [4-(diphenylsulfonio)phenyl] sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl } Sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio ) Phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4 -Benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9 , 10-Dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-(9-oxo-9H-thioxanthene-2- Il) thiophenyl- 9-oxo-9H-thioxanthen-2-ylphenylsulfonium, 4-[4-(4-t-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-t-butylbenzoyl) Phenylthio]phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thiaanthrenium Triarylsulfonium such as 5-phenylthiaanthrenium, 5-tolylthiaanthrenium, 5-(4-ethoxyphenyl)thiaanthrenium, and 5-(2,4,6-trimethylphenyl)thiaanthrenium; diphenylphena Diarylsulfonium such as silsulfonium, diphenyl 4-nitrophenacylsulfonium, diphenylbenzylsulfonium, diphenylmethylsulfonium; phenylmethylbenzylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 4-methoxyphenylmethylbenzylsulfonium, 4-acetocarbonyloxyphenyl Methylbenzylsulfonium, 4-hydroxyphenyl(2-naphthylmethyl)methylsulfonium, 2-naphthylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, phenylmethylphenacylsulfonium, 4-hydroxyphenylmethylphenacyl Mono, such as sulfonium, 4-methoxyphenylmethylphenacylsulfonium, 4-acetocarbonyloxyphenylmethylphenacylsulfonium, 2-naphthylmethylphenacylsulfonium, 2-naphthyloctadecylphenacylsulfonium, 9-anthracenylmethylphenacylsulfonium Arylsulfonium; trialkylsulfonium such as dimethylphenacylsulfonium, phenacyltetrahydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium, octadecylmethylphenacylsulfonium, and the like.

Specific examples of the iodonium ion include diphenyliodonium, di-p-tolyliodonium, bis(4-dodecylphenyl)iodonium, bis(4-methoxyphenyl)iodonium, (4-octyloxyphenyl)phenyliodonium, and bis(4- Decyloxy)phenyliodonium, 4-(2-hydroxytetradecyloxy)phenylphenyliodonium, 4-isopropylphenyl(p-tolyl)iodonium, 4-isobutylphenyl(p-tolyl)iodonium and the like can be mentioned.

In the present invention, the onium borate salts may be used alone or in combination of two or more.
Moreover, you may use together well-known other onium borate salt as needed.
The onium borate salt can be synthesized by a known method described in, for example, JP-A-2014-205624.

The onium borate salt may be previously dissolved in an organic solvent in order to facilitate dissolution in the charge transporting varnish.
Examples of such an organic solvent include carbonates such as propylene carbonate, ethylene carbonate, 1,2-butylene carbonate, dimethyl carbonate and diethyl carbonate; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone and 2-heptanone; ethylene. Such as glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, dipropylene glycol, dipropylene glycol monoacetate monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether or monophenyl ether Polyhydric alcohols and their derivatives; cyclic ethers such as dioxane; ethyl formate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, methyl acetoacetate, ethyl acetoacetate, ethyl pyruvate, Ethyl ethoxyacetate, methyl methoxypropionate, ethyl ethoxypropionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, methyl 2-hydroxy-3-methylbutanoate, 3 -Ethanols such as methoxybutyl acetate and 3-methyl-3-methoxybutyl acetate; aromatic hydrocarbons such as toluene and xylene, and the like, which may be used alone or in combination of two or more kinds. Good.
When an organic solvent is used, its use ratio is preferably 15 to 1000 parts by mass, and more preferably 30 to 500 parts by mass with respect to 100 parts by mass of the onium borate salt.

The charge-transporting substance used in the present invention is not particularly limited, and can be appropriately selected and used from those conventionally known in the field of organic EL and the like.
Specific examples thereof include arylamine derivatives such as oligoaniline derivatives, N,N'-diarylbenzidine derivatives, N,N,N',N'-tetraarylbenzidine derivatives, oligothiophene derivatives, thienothiophene derivatives, thienobenzothiophene. Examples thereof include various hole-transporting substances such as thiophene derivatives such as derivatives and pyrrole derivatives such as oligopyrrole. Among them, arylamine derivatives and thiophene derivatives are preferable, arylamine derivatives are more preferable, and formula (1) or (2 ) An aniline derivative represented by

Further, the molecular weight of the charge transporting substance is not particularly limited, but from the viewpoint of preparing a uniform varnish that gives a thin film having high flatness, 200 to 9,000 is preferable, and the charge transporting property with high solvent resistance is high. From the viewpoint of preparing a uniform varnish which gives a highly flat thin film with high reproducibility, 8,000 or less is more preferable, and 8,000 or less is more preferable and 7,000 or less is more preferable. Is more preferable, 6,000 or less is more preferable, and 5,000 or less is most suitable.
From the viewpoint of preventing the charge-transporting substance from separating when it is made into a thin film, it is preferable that the charge-transporting substance does not have a molecular weight distribution (dispersion degree is 1) (that is, a single molecular weight is preferable. ).

In formula (2), R ¹ and R ² are independently of each other a hydrogen atom, a halogen atom, a nitro group, a cyano group, or an alkyl group having 1 to 20 carbon atoms, which may be substituted with a halogen atom, It represents an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, and specific examples thereof include the above formula (c1 ) And the same groups as those described above.

Among them, R ¹ and R ² are each a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 20 carbon atoms which may be substituted with a halogen atom, or a carbon atom having 6 to 20 carbon atoms which may be substituted with a halogen atom. Is preferred, and a heteroaryl group having 2 to 20 carbon atoms which may be substituted with a halogen atom is preferable, and an alkyl group having 1 to 10 carbon atoms which may be substituted with a hydrogen atom, a fluorine atom, a cyano group or a halogen atom. A group and a phenyl group which may be substituted with a halogen atom are more preferable, a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group are even more preferable, and a hydrogen atom is most suitable.

Ph ¹ in the above formulas (1) and (2) represents a group represented by the formula (P1).

Here, R ^{3 to} R ⁶ are, independently of each other, a hydrogen atom, a halogen atom, a nitro group, a cyano group, or an alkyl group having 1 to 20 carbon atoms, which may be substituted with a halogen atom, or 2 carbon atoms. To alkenyl group having 2 to 20 carbon atoms, alkynyl group having 2 to 20 carbon atoms, aryl group having 6 to 20 carbon atoms or heteroaryl group having 2 to 20 carbon atoms, and specific examples thereof are described in the above formula (c1). The same groups as mentioned above can be mentioned.
In particular, R ^{3 to} R ⁶ are each a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 20 carbon atoms which may be substituted with a halogen atom, or a carbon atom having 6 atoms which may be substituted with a halogen atom. A 20-aryl group and a C2-C20 heteroaryl group which may be substituted with a halogen atom are preferred, and a hydrogen atom, a fluorine atom, a cyano group, and a C1-C10 optionally substituted with a halogen atom. An alkyl group and a phenyl group which may be substituted with a halogen atom are more preferable, a hydrogen atom, a fluorine atom, a methyl group and a trifluoromethyl group are even more preferable, and a hydrogen atom is most suitable.

Specific examples of groups suitable as Ph ^{1 will be} shown below, but the present invention is not limited thereto.

Ar ¹ in the above formula (1) independently represents a group represented by any of the formulas (B1) to (B11), and particularly, any one of the formulas (B1′) to (B11′). The group represented by is preferable.

Here, R ^{7 to} R ²⁷ , R ^{30 to} R ^51, and R ^{53 to} R ¹⁵⁴ may independently of each other be substituted with a hydrogen atom, a halogen atom, a nitro group, a cyano group, or a halogen atom, A diphenylamino group, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms; R ²⁸ and R ²⁹ each independently represent an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with Z ¹ , and R ⁵² represents hydrogen. An atom, an alkyl group having 1 to 20 carbon atoms, optionally substituted by Z ⁴ , an alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms, or optionally substituted by Z ¹ . It represents an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, and Z ¹ has ¹ to 20 carbon atoms, which may be substituted with a halogen atom, a nitro group, a cyano group, or Z ^2. Represents an alkyl group having 2 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms, and Z ² has a carbon number which may be substituted with a halogen atom, a nitro group, a cyano group, or Z ^3. represents a 6-20 aryl group or heteroaryl group having 2 to 20 carbon atoms, Z ³ represents a halogen atom, a nitro group or a cyano group, Z ⁴ is a halogen atom, a nitro group, a cyano group, or Z ^5, Represents an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with, and Z ⁵ is substituted with a halogen atom, a nitro group, a cyano group, or Z ^3. May represent an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms, and these halogen atom, alkyl group having 1 to 20 carbon atoms, and 2 to 20 carbon atoms. Specific examples of the alkenyl group, the alkynyl group having 2 to 20 carbon atoms, the aryl group having 6 to 20 carbon atoms, and the heteroaryl group having 2 to 20 carbon atoms are the same as those described in the above formula (c1). Are listed.

In particular, R ^{7 to} R ²⁷ , R ^{30 to} R ⁵¹ and R ^{53 to} R ¹⁵⁴ are each a hydrogen atom, a fluorine atom, a cyano group, a diphenylamino group which may be substituted with a halogen atom, or a halogen atom. Preferably an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms optionally substituted by a halogen atom, and a heteroaryl group having 2 to 20 carbon atoms optionally substituted by a halogen atom. , A hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 10 carbon atoms which may be substituted with a halogen atom, and a phenyl group which may be substituted with a halogen atom are more preferable, a hydrogen atom, a fluorine atom and methyl. More preferred are groups and trifluoromethyl groups, with hydrogen atoms being most preferred.
As the R ²⁸ and R ^29, an aryl group Z ¹ is carbon atoms and optionally 6-14 substituted with a heteroaryl group are carbon atoms and optionally from 2 to 14 substituted by Z ¹ preferably, Z more preferably an aryl group having 6 to 14 carbon atoms optionally substituted with ^1, a phenyl group which may be substituted with Z ^1, which may be substituted with Z ¹ 1-naphthyl group, substituted with Z ¹ Even more preferred are 2-naphthyl groups.
Then, as R ^52, a hydrogen atom, an aryl group of Z ¹ is carbon atoms and optionally 6-20 substituted the heteroaryl group which may C2-20 optionally substituted by Z ^1, in Z ⁴ alkyl group is preferably a substituted carbon atoms and optionally 1 to 20, a hydrogen atom, Z ¹ in the optionally substituted aryl group having 6 to 14 carbon atoms, Z ¹ carbon atoms which may be substituted by 2 To 14 heteroaryl groups, more preferably alkyl groups having 1 to 10 carbon atoms that may be substituted with Z ⁴ , hydrogen atom, aryl groups having 6 to 14 carbon atoms that may be substituted with Z ¹ , and Z even more preferably an alkyl group which may having 1 to 10 carbon atoms optionally substituted nitrogen-containing heteroaryl group which carbon atoms and optionally from 2 to 14 substituted by Z ⁴ in ^1, hydrogen atom is substituted with Z ¹ Optionally substituted phenyl group, ¹ -naphthyl group optionally substituted with Z ¹ , 2-naphthyl group optionally substituted with Z ¹ , 2-pyridyl group optionally substituted with Z ¹ , Z ^A 3-pyridyl group optionally substituted with ¹ , a 4-pyridyl group optionally substituted with Z ¹ , and a methyl group optionally substituted with Z ⁴ are more preferable.

Ar ⁴ independently represents an aryl group having 6 to 20 carbon atoms which may be substituted with an arylamino group having 6 to 20 carbon atoms.
Specific examples of the aryl group having 6 to 20 carbon atoms and the arylamino group having 6 to 20 carbon atoms include the same groups as those described for the formula (c1).
As Ar ⁴ , phenyl group, 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 9-anthryl group, 1-phenanthryl group, 2-phenanthryl group, 3-phenanthryl group, 4- Phenanthryl group, 9-phenanthryl group, p-(diphenylamino)phenyl group, p-(1-naphthylphenylamino)phenyl group, p-(di(1-naphthyl)amino)phenyl group, p-(1-naphthyl- A 2-naphthylamino)phenyl group and a p-(di(2-naphthyl)amino)phenyl group are preferable, and a p-(diphenylamino)phenyl group is more preferable.

Specific examples of groups suitable as Ar ^{1 will be} shown below, but the invention is not limited thereto.

（式中、Ｒ⁵²は、上記と同じ意味を表す。）

(In the formula, R ⁵² has the same meaning as above.)

Ar ² in the above formula (1) independently represents a group represented by any of the formulas (A1) to (A18).

Here, in the formula, R ¹⁵⁵ is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms or an alkynyl group having 2 to 20 carbon atoms, which may be substituted with Z ⁴ . Or, it represents an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, which may be substituted with Z ¹ , wherein R ¹⁵⁶ and R ¹⁵⁷ are independently substituted with Z ^1. Which may be present, an aryl group having 6 to 20 carbon atoms or a heteroaryl group having 2 to 20 carbon atoms, DPA represents a diphenylamino group, and Ar ⁴ , Z ¹ and Z ⁴ have the same meanings as described above. Of these halogen atoms, alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, alkynyl groups having 2 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms and heteroaryl groups having 2 to 20 carbon atoms. Specific examples thereof include the same groups as those described in the above formula (c1).

Particularly, as the R ^155, a hydrogen atom, an aryl group of Z ¹ is carbon atoms and optionally 6-20 substituted the heteroaryl group which may C2-20 optionally substituted by Z ^1, in Z ⁴ alkyl group is preferably a substituted carbon atoms and optionally 1 to 20, a hydrogen atom, Z ¹ in the optionally substituted aryl group having 6 to 14 carbon atoms, Z ¹ carbon atoms which may be substituted by 2 To 14 heteroaryl groups, more preferably alkyl groups having 1 to 10 carbon atoms that may be substituted with Z ⁴ , hydrogen atom, aryl groups having 6 to 14 carbon atoms that may be substituted with Z ¹ , and Z even more preferably an alkyl group which may having 1 to 10 carbon atoms optionally substituted nitrogen-containing heteroaryl group which carbon atoms and optionally from 2 to 14 substituted by Z ⁴ in ^1, hydrogen atom is substituted with Z ¹ Optionally substituted phenyl group, ¹ -naphthyl group optionally substituted with Z ¹ , 2-naphthyl group optionally substituted with Z ¹ , 2-pyridyl group optionally substituted with Z ¹ , Z ^A 3-pyridyl group optionally substituted with ¹ , a 4-pyridyl group optionally substituted with Z ¹ , and a methyl group optionally substituted with Z ⁴ are more preferable.
As the R ¹⁵⁶ and R ^157, an aryl group Z ¹ is carbon atoms and optionally 6-14 substituted with a heteroaryl group are carbon atoms and optionally from 2 to 14 substituted by Z ¹ preferably, Z more preferably an aryl group having 6 to 14 carbon atoms optionally substituted with ^1, a phenyl group which may be substituted with Z ^1, which may be substituted with Z ¹ 1-naphthyl group, substituted with Z ¹ Even more preferred are 2-naphthyl groups.

Specific examples of groups suitable as Ar ^{2 will be} shown below, but the present invention is not limited thereto.

（式中、Ｒ¹⁵⁵は、上記と同じ意味を表す。）

(In the formula, R ¹⁵⁵ has the same meaning as above.)

In the formula (1), in view of the ease of synthesis of the resulting aniline derivative, Ar ¹ are all the same group, it is preferable that all of Ar ² are identical groups, Ar ¹ and Ar ² It is more preferable that all are the same groups. That is, the aniline derivative represented by the formula (1) is more preferably the aniline derivative represented by the formula (1-1).
In addition, as will be described later, since it can be synthesized relatively easily using relatively inexpensive bis(4-aminophenyl)amine as a raw material compound and has excellent solubility in an organic solvent, the formula (1) The aniline derivative represented is preferably an aniline derivative represented by the formula (1-1).

In formula (1-1), Ph ¹ and k have the same meanings as described above, and Ar ⁵ at the same time represents a group represented by any of formulas (D1) to (D13). It is preferably a group represented by any of D1') to (D13').
Specific examples of Ar ⁵ include the same groups as those described above as specific examples of groups suitable as Ar ¹ .

（式中、Ｒ²⁸、Ｒ²⁹、Ｒ⁵²、Ａｒ⁴およびＤＰＡは、上記と同じ意味を表す。）

(In the formula, R ²⁸ , R ²⁹ , R ⁵² , Ar ⁴ and DPA have the same meanings as described above.)

（式中、Ｒ²⁸、Ｒ²⁹、Ｒ⁵²、Ａｒ⁴およびＤＰＡは、上記と同じ意味を表す。）

(In the formula, R ²⁸ , R ²⁹ , R ⁵² , Ar ⁴ and DPA have the same meanings as described above.)

Further, as will be described later, it can be synthesized relatively easily using a relatively inexpensive bis(4-aminophenyl)amine as a raw material compound, and the obtained aniline derivative has excellent solubility in an organic solvent. The aniline derivative represented by (1) is preferably the aniline derivative represented by the formula (1-2).

The above Ar ⁶ simultaneously represents a group represented by any one of formulas (E1) to (E14).

（式中、Ｒ⁵²は、上記と同じ意味を表す。）

(In the formula, R ⁵² has the same meaning as above.)

Ar ³ in the above formula (2) represents a group represented by any of the formulas (C1) to (C8), and particularly preferably a group represented by any of (C1′) to (C8′). ..

K in the above formula (1) represents an integer of 1 to 10, but from the viewpoint of increasing the solubility of the compound in an organic solvent, 1 to 5 is preferable, 1 to 3 is more preferable, and 1 or 2 is even more preferable. Preferably, 1 is optimum.
L in the above formula (2) represents 1 or 2.

In addition, in R ²⁸ , R ²⁹ , R ⁵² and R ^{155 to} R ¹⁵⁷ , Z ¹ is a halogen atom, a nitro group, a cyano group, an alkyl group having 1 to 10 carbon atoms which may be substituted with Z ² , Z is an alkenyl group having a carbon number of 2 to 10 even if, alkynyl group which may C2-10 optionally substituted by Z ² preferably substituted by ^2, halogen atom, nitro group, cyano group, substituted with Z ² which may be an alkyl group having 1 to 3 carbon atoms, Z ² in which may be substituted an alkenyl group having a carbon number of 2-3, an alkynyl group having carbon atoms which may be have 2-3 substituted with Z ² more preferably, a fluorine atom, an alkyl group having carbon atoms which may be have 1-3 substituted with Z ^2, Z ² substituted by carbon atoms and optionally 2-3 alkenyl group, optionally substituted by Z ² Even more preferred are good alkynyl groups having 2 to 3 carbon atoms.

In R ²⁸ , R ²⁹ , R ^52, and R ^{155 to} R ¹⁵⁷ , Z ⁴ is preferably a halogen atom, a nitro group, a cyano group, or an aryl group having 6 to 14 carbon atoms which may be substituted with Z ⁵ , and is preferably halogen. An atom, a nitro group, a cyano group, and an aryl group having 6 to 10 carbon atoms which may be substituted with Z ⁵ are more preferable, and an aryl group having 6 to 10 carbon atoms which may be substituted with fluorine atom and Z ⁵ are It is even more preferable, and a phenyl group which may be substituted with a fluorine atom or Z ⁵ is further preferable.

In R ^28, R ^29, R ⁵² and R ¹⁵⁵ ~R ^157, Z ² is a halogen atom, a nitro group, a cyano group, Z ³ optionally substituted good having 6 to 14 carbon atoms an aryl group preferably a halogen atom , A nitro group, a cyano group and an aryl group having 6 to 10 carbon atoms which may be substituted with Z ³ are more preferable, and a fluorine atom and an aryl group having 6 to 10 carbon atoms which may be substituted with Z ³ are more preferable. More preferred is a phenyl group which may be substituted with a fluorine atom or Z ³ , and further preferred.

In R ^28, R ^29, R ⁵² and R ¹⁵⁵ ~R ^157, Z ⁵ is a halogen atom, a nitro group, a cyano group, Z ³ optionally substituted by an alkyl group having 1 to 10 carbon atoms, with Z ³ An alkenyl group having 2 to 10 carbon atoms which may be substituted and an alkynyl group having 2 to 10 carbon atoms which may be substituted with Z ³ are preferable, and substituted with a halogen atom, a nitro group, a cyano group or Z ^3. an alkyl group having 1 to 3 carbon atoms which can, Z ^{3-substituted} carbon atoms and optionally 2-3 alkenyl group, Z ³ and more preferably an alkynyl group having carbon atoms which may 2-3 optionally substituted by , a fluorine atom, Z ³ in the optionally substituted alkyl group having 1 to 3 carbon atoms, Z ^{3-substituted} carbon atoms and optionally 2-3 alkenyl group, optionally substituted by Z ³ carbon The alkynyl group of the number 2 to 3 is even more preferable.

In R ²⁸ , R ²⁹ , R ⁵² and R ^{155 to} R ¹⁵⁷ , Z ³ is preferably a halogen atom, and more preferably a fluorine atom.

On the other hand, in R ^{7 to} R ²⁷ , R ^{30 to} R ^51, and R ^{53 to} R ¹⁵⁴ , Z ¹ is a halogen atom, a nitro group, a cyano group, or an alkyl group having 1 to 3 carbon atoms which may be substituted with Z ^2. group, an alkenyl group carbon atoms which may be have 2-3 substituted with Z ^2, an alkynyl group having a carbon number of 2-3 is preferable optionally substituted by Z ^2, a halogen atom, optionally substituted by Z ² A C1-C3 alkyl group is more preferable, and a fluorine atom or a methyl group optionally substituted with Z ² is even more preferable.

In R ^{7 to} R ²⁷ , R ^{30 to} R ^51, and R ^{53 to} R ¹⁵⁴ , Z ⁴ is a halogen atom, a nitro group, a cyano group, or an aryl group having 6 to 10 carbon atoms which may be substituted with Z ^5. Of these, a halogen atom and an aryl group having 6 to 10 carbon atoms which may be substituted with Z ⁵ are more preferable, and a phenyl group which may be substituted with a fluorine atom and Z ⁵ are even more preferable.

In R ^{7 to} R ²⁷ , R ^{30 to} R ^51, and R ^{53 to} R ¹⁵⁴ , Z ² is a halogen atom, a nitro group, a cyano group, or an aryl group having 6 to 10 carbon atoms which may be substituted with Z ^3. Of these, a halogen atom and an aryl group having 6 to 10 carbon atoms which may be substituted with Z ³ are more preferable, and a phenyl group which may be substituted with a fluorine atom and Z ³ are even more preferable.

In R ^{7 to} R ²⁷ , R ^{30 to} R ⁵¹ and R ^{53 to} R ¹⁵⁴ , Z ⁵ is a halogen atom, a nitro group, a cyano group, or an alkyl group having 1 to 3 carbon atoms which may be substituted with Z ³ . Z ³ in which may be substituted an alkenyl group having a carbon number of 2-3, an alkynyl group having a carbon number of 2-3 is preferable optionally substituted by Z ^3, halogen atom, optionally substituted by Z ³ An alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group optionally substituted with a fluorine atom or Z ³ is even more preferable.

In R ^{7 to} R ²⁷ , R ^{30 to} R ^51, and R ^{53 to} R ¹⁵⁴ , Z ³ is preferably a halogen atom, and more preferably a fluorine atom.

Specific examples of the groups suitable as R ⁵² and R ¹⁵⁵ include the following groups, but are not limited thereto.

The alkyl group, alkenyl group and alkynyl group preferably have 10 or less carbon atoms, more preferably 6 or less carbon atoms, and even more preferably 4 or less carbon atoms.
The aryl group and the heteroaryl group preferably have 14 or less carbon atoms, more preferably 10 or less carbon atoms, and even more preferably 6 or less carbon atoms.

The aniline derivative represented by the above formula (1) can be produced by reacting the amine compound represented by the formula (3) with the aryl compound represented by the formula (4) in the presence of a catalyst.

（式中、Ｘは、ハロゲン原子または擬ハロゲン基を表し、Ａｒ¹、Ａｒ²、Ｐｈ¹およびｋは、上記と同じ意味を表す。）

(In the formula, X represents a halogen atom or a pseudohalogen group, and Ar ¹ , Ar ² , Ph ¹ and k have the same meanings as described above.)

In particular, the aniline derivative represented by the formula (1-1) can be produced by reacting the amine compound represented by the formula (5) with the aryl compound represented by the formula (6) in the presence of a catalyst. ..

（式中、Ｘ、Ａｒ⁵、Ｐｈ¹およびｋは、上記と同じ意味を表す。）

(In the formula, X, Ar ⁵ , Ph ¹ and k have the same meanings as described above.)

Further, the aniline derivative represented by the formula (1-2) can be produced by reacting bis(4-aminophenyl)amine with the aryl compound represented by the formula (7) in the presence of a catalyst.

（式中、ＸおよびＡｒ⁶は、上記と同じ意味を表す。）

(In the formula, X and Ar ⁶ have the same meanings as described above.)

On the other hand, the aniline derivative represented by the above formula (2) can be produced by reacting the amine compound represented by the formula (8) with the aryl compound represented by the formula (9) in the presence of a catalyst.

（式中、Ｘ、Ｒ¹、Ｒ²、Ａｒ³、Ｐｈ¹およびｌは、上記と同じ意味を表す。）

(In the formula, X, R ¹ , R ² , Ar ³ , Ph ¹ and l have the same meanings as described above.)

Examples of the halogen atom are the same as those mentioned above.
Pseudohalogen groups include (fluoro)alkylsulfonyloxy groups such as methanesulfonyloxy group, trifluoromethanesulfonyloxy group, nonafluorobutanesulfonyloxy group; aromatic sulfonyloxy groups such as benzenesulfonyloxy group, toluenesulfonyloxy group, etc. Are listed.

An amine compound represented by formula (3), (5) or (8) or bis(4-aminophenyl)amine, and an aryl represented by formula (4), (6), (7) or (9) The charge ratio of the compound to the compound may be equal to or more than the amount of the aryl compound with respect to the amount of all NH groups of the amine compound or bis(4-aminophenyl)amine, but is preferably about 1 to 1.2 equivalents. is there.

Examples of the catalyst used in the above reaction include copper catalysts such as copper chloride, copper bromide, copper iodide; Pd(PPh ₃ ) ₄ (tetrakis(triphenylphosphine)palladium), Pd(PPh ₃ ) ₂ Cl ₂ (bis(triphenylphosphine)dichloropalladium), Pd(dba) ₂ (bis(dibenzylideneacetone)palladium), Pd ₂ (dba) ₃ (tris(dibenzylideneacetone)dipalladium), Pd(Pt) Examples thereof include palladium catalysts such as —Bu ₃ ) ₂ (bis(tri(t-butylphosphine))palladium) and Pd(OAc) ₂ (palladium acetate). These catalysts may be used alone or in combination of two or more. Further, these catalysts may be used together with a known appropriate ligand.
Examples of such a ligand include triphenylphosphine, tri-o-tolylphosphine, diphenylmethylphosphine, phenyldimethylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, tri-tert-butylphosphine. Fin, di-t-butyl(phenyl)phosphine, di-tert-butyl(4-dimethylaminophenyl)phosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, Tertiary phosphines such as 1,4-bis(diphenylphosphino)butane and 1,1′-bis(diphenylphosphino)ferrocene, and tertiary phosphites such as trimethylphosphite, triethylphosphite and triphenylphosphite are available. Can be mentioned.

The amount of the catalyst used can be set to about 0.2 mol, preferably about 0.15 mol, relative to 1 mol of the aryl compound represented by the formula (4), (6), (7) or (9). Is.
Further, when a ligand is used, the amount thereof used can be 0.1 to 5 equivalents with respect to the metal complex used, but 1 to 2 equivalents is preferable.

Each of the above reactions is carried out in a solvent when all the raw material compounds are solid or from the viewpoint of efficiently obtaining the desired aniline derivative. When a solvent is used, its type is not particularly limited as long as it does not adversely affect the reaction. As specific examples, aliphatic hydrocarbons (pentane, n-hexane, n-octane, n-decane, decalin, etc.), halogenated aliphatic hydrocarbons (chloroform, dichloromethane, dichloroethane, carbon tetrachloride, etc.), aromatic Group hydrocarbons (benzene, nitrobenzene, toluene, o-xylene, m-xylene, p-xylene, mesitylene, etc.), halogenated aromatic hydrocarbons (chlorobenzene, bromobenzene, o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene etc.), ethers (diethyl ether, diisopropyl ether, t-butyl methyl ether, tetrahydrofuran, dioxane, 1,2-dimethoxyethane, 1,2-diethoxyethane etc.), ketones (acetone, methyl ethyl ketone, Methyl isobutyl ketone, di-n-butyl ketone, cyclohexanone, etc.), amides (N,N-dimethylformamide, N,N-dimethylacetamide, etc.), lactams and lactones (N-methylpyrrolidone, γ-butyrolactone, etc.), urea (N,N-dimethylimidazolidinone, tetramethylurea, etc.), sulfoxides (dimethyl sulfoxide, sulfolane, etc.), nitrites (acetonitrile, propionitrile, butyronitrile, etc.), etc., and these solvents are used alone. They may be used or two or more kinds may be mixed and used.

The reaction temperature may be appropriately set in the range from the melting point to the boiling point of the solvent used, but is preferably about 0 to 200°C, more preferably 20 to 150°C.
After the completion of the reaction, the desired aniline derivative can be obtained by post-treatment according to a conventional method.

In the method for producing the aniline derivative represented by the above formula (1), the amine compound represented by the formula (3′) that can be used as a raw material is the amine compound represented by the formula (10) and the formula (11). The aryl compound represented by can be efficiently produced by reacting with an aryl compound in the presence of a catalyst.

（式中、Ｘ、Ａｒ¹、Ｐｈ¹およびｋは、上記と同じ意味を表す。ただし、２つのＡｒ¹が同時に式（Ｂ１）で表される基となることはない。）

(In the formula, X, Ar ¹ , Ph ¹ and k have the same meanings as described above. However, two Ar ¹ 's are not a group represented by the formula (B1) at the same time.)

In the above-mentioned method for producing the amine compound represented by the formula (3′), the amine compound represented by the formula (10) and the aryl compound represented by the formula (11) are subjected to a coupling reaction. Regarding the charging of the amine compound represented by the formula (10) and the aryl compound represented by the formula (11), the aryl compound is preferably about 2 to 2.4 with respect to the amine compound 1 in terms of the substance amount ratio. is there.
In addition, various conditions regarding the catalyst, the ligand, the solvent, the reaction temperature, and the like in the coupling reaction are the same as the above-described conditions described for the method for producing the aniline derivative represented by the formula (1).

In the formula (1), Ar ¹ is a group represented by the formula (B4) or a group represented by the formula (B10) in which R ⁵² is a hydrogen atom, or Ar ² is a group represented by the formula (B4). In the case of producing an aniline derivative which is a group represented by A12) or a group represented by Formula (A16) in which R ¹⁵⁵ (including R ⁵² in Formula (1-1)) is a hydrogen atom, the above reaction In, an aryl compound having a known protecting group on the amino group may be used.

Specific examples of the aniline derivative represented by the formula (1) or (2) are shown below, but the invention is not limited thereto. In the formulas and tables, "Me" represents a methyl group, "Et" represents an ethyl group, a "Pr ^n" is n- propyl group, "Pr ^i" is i- propyl group, "Bu ^n" is the n- butyl group, "Bu ^i" is i- butyl group, "Bu ^s" is s- butyl group, "Bu ^t" is t- butyl group, "DPA" refers diphenylamino group, "SBF "Represents a 9,9'-spirobi[9H-fluoren]-2-yl group, respectively.

In the present invention, the ratio of the onium borate salt to the charge transporting substance may be a charge transporting substance:onium borate salt=1:0.1 to 10 in terms of a substance amount (molar ratio).

As the organic solvent used when preparing the charge-transporting varnish, a highly soluble solvent capable of favorably dissolving the charge-transporting substance and the onium borate salt can be used.
Examples of such a highly soluble solvent include cyclohexanone, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, and diethylene glycol monomethyl ether. Organic solvents are included, but are not limited to. These solvents can be used alone or in combination of two or more, and the amount thereof used can be 5 to 100 mass% with respect to the entire solvent used in the varnish.

Further, in the present invention, the varnish has a viscosity of 10 to 200 mPa·s at 25° C., especially 35 to 150 mPa·s, and a boiling point of 50 to 300° C., particularly 150 to 250° C. at normal pressure (atmospheric pressure). By containing at least one high-viscosity organic solvent, it becomes easy to adjust the viscosity of the varnish, and as a result, it becomes possible to prepare a varnish according to the coating method, which gives a thin film having high flatness with good reproducibility.
Examples of the high-viscosity organic solvent include cyclohexanol, ethylene glycol, ethylene glycol diglycidyl ether, 1,3-octylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, 1,3-butanediol, Examples thereof include 2,3-butanediol, 1,4-butanediol, propylene glycol, and hexylene glycol, but are not limited thereto. These solvents may be used alone or in combination of two or more.
The addition ratio of the high-viscosity organic solvent to the entire solvent used in the varnish of the present invention is preferably within a range in which solid does not precipitate, and the addition ratio is preferably 5 to 90 mass% as long as solid does not precipitate.

Further, for the purpose of improving the wettability with respect to the substrate, adjusting the surface tension of the solvent, adjusting the polarity, adjusting the boiling point, etc., other solvents are used in an amount of 1 to 90% by mass, preferably 1 to 90% by mass, based on the whole solvent used for the varnish. It is also possible to mix at a ratio of 1 to 50% by mass.
Examples of such a solvent include propylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol. Examples thereof include, but are not limited to, monoethyl ether, diacetone alcohol, γ-butyrolactone, ethyl lactate, and n-hexyl acetate. These solvents can be used alone or in combination of two or more.

The charge-transporting varnish of the present invention may contain an organic silane compound. When the thin film obtained from the varnish is used as the hole injecting layer of the organic EL device by including the organic silane compound, the hole injecting layer should be in contact with the hole injecting layer on the side opposite to the anode such as the hole transporting layer or the light emitting layer. It is possible to enhance the hole injecting ability into the layer laminated on the.
Examples of the organosilane compound include dialkoxysilane compounds, trialkoxysilane compounds, and tetraalkoxysilane compounds, and these may be used alone or in combination of two or more kinds.
In the present invention, the organosilane compound preferably contains one kind selected from a dialkoxysilane compound and a trialkoxysilane compound, more preferably contains a trialkoxysilane compound, and contains a fluorine atom-containing trialkoxysilane compound. It is even more preferable.

Examples of these alkoxysilane compounds include those represented by the formulas (S1) to (S3).
Si(OR) ₄ (S1)
SiR'(OR) ₃ (S2)
Si(R') ₂ (OR) ₂ (S3)

In the formula, R independently of one another, an alkyl group having carbon atoms which may be have 1-20 substituted with Z ^6, an alkenyl group optionally having 2 to 20 carbon atoms optionally substituted by Z ^6, with Z ⁶ an optionally substituted alkynyl group having a carbon number of 2 to 20, Z ^{7-substituted} having 6 to 20 carbon atoms which may have an aryl group or a heteroaryl good 2 to 20 carbon atoms optionally substituted by Z ^7, represents an aryl group, R 'independently of one another, Z ⁸ alkyl group carbon atoms which may be have 1 to 20 substituted by an alkenyl group which may C2-20 optionally substituted by Z ^8, alkynyl group optionally 2 to 20 carbon atoms optionally substituted by Z ^8, which may be substituted aryl group having 6 to 20 carbon atoms in Z ⁹ or Z ⁹ carbon atoms, which may be substituted by 2, Represents 20 heteroaryl groups.

Z ⁶ represents a halogen atom, represents a heteroaryl group Z ¹⁰ in which may be substituted aryl group having 6 to 20 carbon atoms, or optionally 2 to 20 carbon atoms optionally substituted by Z ^10,, Z ⁷ is a halogen atom, may be substituted with Z ¹⁰ in the optionally substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group which may C2-20 optionally substituted by Z ¹⁰ or Z ^10, It represents an alkynyl group having 2 to 20 carbon atoms.

Z ⁸ represents a halogen atom, Z ^{10-substituted} having 6 to 20 carbon atoms which may have an aryl group, a heteroaryl group which may C2-20 optionally substituted by Z ^10, epoxycyclohexyl group, a glycidoxy group , A methacryloxy group, an acryloxy group, a ureido group (-NHCONH ₂ ), a thiol group, an isocyanate group (-NCO), an amino group, a -NHY ¹ group, or a -NY ² Y ³ group, Z ⁹ is a halogen atom, alkyl group carbon atoms which may be have 1-20 replaced by Z ^10, Z ¹⁰ in which may be substituted an alkenyl group having a carbon number of 2 to 20, carbon atoms which may be substituted with Z ¹⁰ 2-20 alkynyl group, an epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, an acryloxy group, a ureido group (-NHCONH _2), thiol group, isocyanate group (-NCO), amino group, -NHY ¹ group, or -NY ² Y ³ group the stands, Y ¹ to Y ^3, independently of one another, Z ¹⁰ in the optionally substituted alkyl group having 1 to 20 carbon atoms, an alkenyl group which may C2-20 optionally substituted by Z ¹⁰ , Z ¹⁰ in optionally substituted alkynyl group having a carbon number of 2 to 20, Z ^{10-substituted} having 6 to 20 carbon atoms which may have an aryl group or Z ¹⁰ carbon atoms which may be substituted by 2, ~ 20 heteroaryl groups.
Z ¹⁰ represents a halogen atom, an amino group, a nitro group, a cyano group or a thiol group.

In the formulas (S1) to (S3), a halogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and Examples of the heteroaryl group having 2 to 20 carbon atoms include the same ones as described above.
In R and R′, the alkyl group, alkenyl group and alkynyl group preferably have 10 or less carbon atoms, more preferably 6 or less carbon atoms, and even more preferably 4 or less carbon atoms.
The aryl group and the heteroaryl group preferably have 14 or less carbon atoms, more preferably 10 or less carbon atoms, and even more preferably 6 or less carbon atoms.

R is an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms which may be substituted with Z ⁶ , or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ^7. Is more preferable, an alkyl group having 1 to 6 carbon atoms or an alkenyl group having 2 to 6 carbon atoms that may be substituted with Z ⁶ , or a phenyl group that may be substituted with Z ⁷ is more preferable, and Z ⁶ is An alkyl group having 1 to 4 carbon atoms which may be substituted or a phenyl group which may be substituted with Z ⁷ is further preferable, and a methyl group or an ethyl group which may be substituted with Z ⁶ is further preferable.
R′ is preferably an alkyl group having 1 to 20 carbon atoms which may be substituted with Z ⁸ or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ⁹ , and is substituted with Z ^8. More preferably an alkyl group having 1 to 10 carbon atoms which may be substituted or an aryl group having 6 to 14 carbon atoms which may be substituted with Z ⁹ , and an alkyl group having 1 to 6 carbon atoms which may be substituted with Z ^8. A group or an aryl group having 6 to 10 carbon atoms which may be substituted with Z ⁹ is more preferable, and an alkyl group having 1 to 4 carbon atoms which may be substituted with Z ⁸ or substituted with Z ^9. Further preferred are phenyl groups.
It should be noted that the plurality of R's may all be the same or different, and the plurality of R'may all be the same or different.

As Z ⁶ , a halogen atom or an aryl group having 6 to 20 carbon atoms which may be substituted with Z ¹⁰ is preferable, and a phenyl group which may be substituted with a fluorine atom or Z ¹⁰ is more preferable. That is, non-substitution) is optimal.
As the Z ^7, halogen atom or Z preferably is an alkyl group having 6 to 20 carbon atoms which may be substituted with ^10, a fluorine atom or an alkyl group of carbon atoms which may be have 1 to 10 substituted by Z ¹⁰ Is more preferred, and the absence (ie, non-substitution) is optimal.

On the other hand, the Z ^8, a halogen atom, Z a phenyl group optionally substituted with ^10, good furanyl group optionally substituted by Z ^10, epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, an acryloxy group, a ureido group, thiol group, isocyanate group, an amino group, an optionally substituted phenylamino group Z ¹⁰ or better diphenylamino group optionally substituted by Z ¹⁰ is preferably, more preferably a halogen atom, a fluorine atom or absent, (I.e., non-substituted) is even more preferable.
As the Z ^9, a halogen atom, Z ^{10-substituted} carbon atoms and optionally 1 to 20 alkyl group, Z ¹⁰ in which may be substituted furanyl group, an epoxycyclohexyl group, a glycidoxy group, a methacryloxy group, acryloxy group, ureido group, a thiol group, isocyanate group, amino group, optionally diphenylamino group preferably be substituted with a which may phenylamino group optionally or Z ^10, substituted with Z ^10, more preferably a halogen atom, It is even more preferable that the atom be a fluorine atom or not be present (that is, be unsubstituted).
Z ¹⁰ is preferably a halogen atom, more preferably a fluorine atom or absent (that is, unsubstituted).

Specific examples of the organic silane compound that can be used in the present invention will be given below, but the invention is not limited thereto.
Specific examples of the dialkoxysilane compound include dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylpropyldimethoxysilane, methylpropyldiethoxysilane, diisopropyldimethoxysilane, and phenylmethyl. Dimethoxysilane, vinylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 3-methacryloxy Propylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-mercaptopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)aminopropylmethyldimethoxysilane, 3,3,3 3-trifluoropropyl methyldimethoxysilane etc. are mentioned.

Specific examples of the trialkoxysilane compound, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, Pentyltrimethoxysilane, Pentyltriethoxysilane, Heptyltrimethoxysilane, Heptyltriethoxysilane, Octyltrimethoxysilane, Octyltriethoxysilane, Dodecyltrimethoxysilane, Dodecyltriethoxysilane, Hexadecyltrimethoxysilane, Hexadecyltriethoxysilane Silane, octadecyltrimethoxysilane, octadecyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, γ- Glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, triethoxy(4-(trifluoromethyl)phenyl)silane, dodecyl Triethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, (triethoxysilyl)cyclohexane, perfluorooctylethyltriethoxysilane, triethoxyfluorosilane, tridecafluoro-1,1,2,2-tetrahydro Octyltriethoxysilane, pentafluorophenyltrimethoxysilane, pentafluorophenyltriethoxysilane, 3-(heptafluoroisopropoxy)propyltriethoxysilane, heptadecafluoro-1,1,2,2-tetrahydrodecyltriethoxysilane, Examples thereof include triethoxy-2-thienylsilane and 3-(triethoxysilyl)furan.

Specific examples of the tetraalkoxysilane compound include tetraethoxysilane, tetramethoxysilane, tetrapropoxysilane and the like.

Among these, 3,3,3-trifluoropropylmethyldimethoxysilane, triethoxy(4-(trifluoromethyl)phenyl)silane, 3,3,3-trifluoropropyltrimethoxysilane, perfluorooctylethyltriethoxysilane Alternatively, pentafluorophenyltrimethoxysilane and pentafluorophenyltriethoxysilane are preferable.

When the charge-transporting varnish of the present invention contains an organic silane compound, its content is usually relative to the mass of the charge-transporting substance (when the dopant substance is included, the total mass of the charge-transporting substance and the dopant substance). Although it is about 0.1 to 50% by mass, it is possible to suppress the deterioration of the charge transport property of the obtained thin film, and to contact the above-mentioned cathode side with the hole injection layer or the like made of the thin film obtained from the varnish. Considering to enhance the hole injection ability to the layer to be laminated, it is preferably about 0.5 to 40% by mass, more preferably about 0.8 to 30% by mass, still more preferably about 1 to 20% by mass. Is.

The viscosity of the varnish of the present invention is appropriately set according to the thickness of the thin film to be produced and the solid content concentration, but is usually 1 to 50 mPa·s at 25° C., and its surface tension is usually 20 to 50 mN/m.
The solid content concentration of the charge transporting varnish is appropriately set in consideration of the viscosity and surface tension of the varnish, the thickness of the thin film to be produced, etc., but is usually 0.1 to 10.0 mass. %, and from the viewpoint of improving the coating property of the varnish, it is preferably about 0.5 to 5.0% by mass, more preferably about 1.0 to 3.0% by mass.

The method for preparing the varnish is not particularly limited, but, for example, a method in which the onium borate salt is first dissolved in a solvent and a charge transporting substance is sequentially added thereto, or the onium borate salt and the charge transporting property are sequentially added. Examples include a method of dissolving a mixture with a substance in a solvent.
Further, when there are a plurality of organic solvents, for example, in the solvent which dissolves the above-mentioned onium borate salt and the charge transporting substance well, these are first dissolved, and other solvent may be added thereto, and a plurality of organic solvents may be added. The onium borate salt and the charge transporting substance may be sequentially dissolved in the mixed solvent, or these may be simultaneously dissolved.

In the present invention, the charge-transporting varnish uses a submicro-order filter or the like after dissolving the onium borate salt, the charge-transporting compound, or the like in an organic solvent, from the viewpoint of obtaining a highly flat thin film with good reproducibility. It is desirable to filter.

The charge-transporting thin film of the present invention can be formed on a substrate by applying the above-described charge-transporting varnish onto a substrate and baking the varnish.
The method for applying the varnish is not particularly limited, and examples thereof include a dipping method, a spin coating method, a transfer printing method, a roll coating method, a brush coating method, an inkjet method, a spray method, and a slit coating method. It is preferable to adjust the viscosity and surface tension of the varnish accordingly.

Further, when using the varnish of the present invention, the firing atmosphere is not particularly limited, and a thin film having a uniform film-forming surface and a high charge-transporting property can be formed not only in the air atmosphere but also in an inert gas such as nitrogen or vacuum. Although it can be obtained, depending on the type of the charge transporting compound or the like, it may be possible to reproducibly obtain a thin film having a higher charge transporting property by firing the varnish in an air atmosphere.

Although the firing temperature is appropriately set within the range of about 100 to 260° C. in consideration of the use of the obtained thin film, the degree of charge transport property imparted to the obtained thin film, the type of solvent and the boiling point, etc. When the obtained thin film is used as a hole injection layer of an organic EL device, the temperature is preferably about 140 to 250°C, more preferably about 145 to 240°C.
It should be noted that the temperature may be changed in two or more steps for the purpose of exhibiting a higher uniform film-forming property or advancing the reaction on the base material during the baking. It suffices to use an appropriate device such as an oven.

The thickness of the charge transporting thin film is not particularly limited, but when used as a hole injection layer, a hole transport layer or a hole injection transport layer of an organic EL device, it is preferably 5 to 200 nm. As a method of changing the film thickness, there are methods such as changing the solid content concentration in the varnish and changing the amount of the solution on the substrate at the time of coating.

The organic EL device of the present invention has a pair of electrodes, and the charge transporting thin film of the present invention described above between the electrodes.
Typical configurations of the organic EL element include the following (a) to (f), but are not limited thereto. In the following configuration, if necessary, an electron blocking layer or the like may be provided between the light emitting layer and the anode, and a hole (hole) blocking layer or the like may be provided between the light emitting layer and the cathode. Further, the hole injecting layer, the hole transporting layer or the hole injecting and transporting layer may also have a function as an electron blocking layer, and the electron injecting layer, the electron transporting layer or the electron injecting and transporting layer may be holes (holes). You may also have the function as a block layer etc.
(A) Anode/hole injecting layer/hole transporting layer/light emitting layer/electron transporting layer/electron injecting layer/cathode (b) anode/hole injecting layer/hole transporting layer/light emitting layer/electron injecting/transporting layer/ Cathode (c) Anode/hole injecting/transporting layer/light emitting layer/electron transporting layer/electron injecting layer/cathode (d) anode/hole injecting/transporting layer/light emitting layer/electron injecting/transporting layer/cathode (e) anode/positive Hole injection layer/hole transport layer/light emitting layer/cathode (f) Anode/hole injection/transport layer/light emitting layer/cathode

The "hole injection layer", "hole transport layer" and "hole injection transport layer" are layers formed between a light emitting layer and an anode, and transport holes from the anode to the light emitting layer. In the case where only one layer of a hole-transporting material is provided between the light-emitting layer and the anode, which has a function, it is a “hole-injecting and transporting layer”, and between the light-emitting layer and the anode, When two or more layers of the hole transporting material are provided, the layer close to the anode is the “hole injecting layer” and the other layers are the “hole transporting layer”. In particular, as the hole injecting (transporting) layer, a thin film having excellent hole injecting property to the hole transporting (light emitting) layer as well as the hole accepting property from the anode is used.
"Electron injection layer", "electron transport layer" and "electron injection transport layer" are layers formed between a light emitting layer and a cathode and having a function of transporting electrons from the cathode to the light emitting layer. When only one layer of the electron transporting material is provided between the light emitting layer and the cathode, it is an “electron injecting and transporting layer”, and a layer of the electron transporting material is provided between the light emitting layer and the cathode. When two or more layers are provided, the layer close to the cathode is the “electron injection layer” and the other layers are the “electron transport layer”.
The “light emitting layer” is an organic layer having a light emitting function and includes a host material and a dopant material when a doping system is adopted. At this time, the host material mainly has a function of promoting recombination of electrons and holes and confining excitons in the light-emitting layer, and the dopant material efficiently emits excitons obtained by the recombination. Have a function. In the case of a phosphorescent device, the host material has a function of mainly confining excitons generated by the dopant in the light emitting layer.

The charge transporting thin film of the present invention can be suitably used as a hole injection layer, a hole transport layer, and a hole injection transport layer in an organic EL device, and can be more preferably used as a hole injection layer.

Examples of materials used and methods for producing an organic EL device using the charge-transporting varnish of the present invention include, but are not limited to, the following.
The electrode substrate to be used is preferably cleaned in advance by cleaning with a liquid such as detergent, alcohol, pure water, etc. For example, the anode substrate is subjected to surface treatment such as UV ozone treatment and oxygen-plasma treatment immediately before use. It is preferable. However, when the anode material contains an organic material as a main component, surface treatment may not be performed.

An example of a method for producing an organic EL device having a hole injection layer composed of a thin film obtained from the charge transporting varnish of the present invention is as follows.
By the above method, the charge transporting varnish of the present invention is applied onto the anode substrate and baked to form a hole injection layer on the electrode.
A hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a cathode are provided in this order on this hole injection layer. The hole-transporting layer, the light-emitting layer, the electron-transporting layer, and the electron-injecting layer may be formed by any one of an evaporation method and a coating method (wet process) depending on characteristics of a material used.
Examples of the anode material include a transparent electrode typified by indium tin oxide (ITO) and indium zinc oxide (IZO), and a metal anode composed of a metal typified by aluminum or an alloy thereof. Those subjected to a chemical treatment are preferable. A polythiophene derivative or a polyaniline derivative having a high charge transporting property can also be used.
The other metals constituting the metal anode include scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, gallium, yttrium, zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, cadmium. , Indium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, hafnium, thallium, tungsten, rhenium, osmium, iridium, platinum, gold, titanium, lead , Bismuth, alloys thereof, and the like, but are not limited to these.

As the material for forming the hole transport layer, (triphenylamine) dimer derivative, [(triphenylamine) dimer] spiro dimer, N,N'-bis(naphthalen-1-yl)-N,N'-bis (Phenyl)-benzidine (α-NPD), N,N′-bis(naphthalen-2-yl)-N,N′-bis(phenyl)-benzidine, N,N′-bis(3-methylphenyl)- N,N'-bis(phenyl)-benzidine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-9,9-spirobifluorene, N,N'-bis( Naphthalen-1-yl)-N,N'-bis(phenyl)-9,9-spirobifluorene, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-9, 9-Dimethyl-fluorene, N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-9,9-dimethyl-fluorene, N,N'-bis(3-methylphenyl) -N,N'-bis(phenyl)-9,9-diphenyl-fluorene, N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-9,9-diphenyl-fluorene , N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine, 2,2',7,7'-tetrakis(N,N-diphenyl) Amino)-9,9-spirobifluorene, 9,9-bis[4-(N,N-bis-biphenyl-4-yl-amino)phenyl]-9H-fluorene, 9,9-bis[4-( N,N-bis-naphthalen-2-yl-amino)phenyl]-9H-fluorene, 9,9-bis[4-(N-naphthalen-1-yl-N-phenylamino)-phenyl]-9H-fluorene ,2,2',7,7'-Tetrakis[N-naphthalenyl(phenyl)-amino]-9,9-spirobifluorene, N,N'-bis(phenanthrene-9-yl)-N,N'- Bis(phenyl)-benzidine, 2,2'-bis[N,N-bis(biphenyl-4-yl)amino]-9,9-spirobifluorene, 2,2'-bis(N,N-diphenylamino) )-9,9-Spirobifluorene, di-[4-(N,N-di(p-tolyl)amino)-phenyl]cyclohexane, 2,2',7,7'-tetra(N,N-di) (P-Tolyl))amino-9,9-spirobifluorene, N,N,N′,N′-tetra-naphthalen-2-yl-benzidine, N , N,N',N'-tetra-(3-methylphenyl)-3,3'-dimethylbenzidine, N,N'-di(naphthalenyl)-N,N'-di(naphthalen-2-yl)- Benzidine, N,N,N′,N′-tetra(naphthalenyl)-benzidine, N,N′-di(naphthalen-2-yl)-N,N′-diphenylbenzidine-1,4-diamine, N ¹ , N ⁴ - diphenyl -N ^1, N ⁴ - di (m-tolyl) ^{benzene-1,4-diamine, N 2, N 2, N} 6, N 6 - tetraphenyl-2,6-diamine, tris (4 -(Quinolin-8-yl)phenyl)amine, 2,2'-bis(3-(N,N-di(p-tolyl)amino)phenyl)biphenyl, 4,4',4"-tris[3- Triarylamines such as methylphenyl(phenyl)amino]triphenylamine (m-MTDATA), 4,4′,4″-tris[1-naphthyl(phenyl)amino]triphenylamine (1-TNATA), 5 , 5"-Bis-{4-[bis(4-methylphenyl)amino]phenyl}-2,2':5',2"-terthiophene (BMA-3T) and other hole transporting agents such as oligothiophenes Low molecular weight materials.

As a material for forming the light emitting layer, tris (8-quinolinolato) aluminum (III) (Alq _3), bis (8-quinolinolato) zinc (II) (Znq _2), bis (2-methyl-8-quinolinolato) - 4-(p-phenylphenolato)aluminum(III)(BAlq), 4,4'-bis(2,2-diphenylvinyl)biphenyl, 9,10-di(naphthalen-2-yl)anthracene, 2-t -Butyl-9,10-di(naphthalen-2-yl)anthracene, 2,7-bis[9,9-di(4-methylphenyl)-fluoren-2-yl]-9,9-di(4- Methylphenyl)fluorene, 2-methyl-9,10-bis(naphthalen-2-yl)anthracene, 2-(9,9-spirobifluoren-2-yl)-9,9-spirobifluorene, 2,7 -Bis(9,9-spirobifluoren-2-yl)-9,9-spirobifluorene, 2-[9,9-di(4-methylphenyl)-fluoren-2-yl]-9,9- Di(4-methylphenyl)fluorene, 2,2'-dipyrenyl-9,9-spirobifluorene, 1,3,5-tris(pyren-1-yl)benzene, 9,9-bis[4-(pyrenyl) )Phenyl]-9H-fluorene, 2,2'-bi(9,10-diphenylanthracene), 2,7-dipyrenyl-9,9-spirobifluorene, 1,4-di(pyren-1-yl)benzene 1,3-di(pyren-1-yl)benzene, 6,13-di(biphenyl-4-yl)pentacene, 3,9-di(naphthalen-2-yl)perylene, 3,10-di(naphthalene) -2-yl)perylene, tris[4-(pyrenyl)-phenyl]amine, 10,10'-di(biphenyl-4-yl)-9,9'-bianthracene, N,N'-di(naphthalene-) 1-yl)-N,N′-diphenyl-[1,1′:4′,1″:4″,1′″-quatphenyl]-4,4″′-diamine, 4,4 '-Di[10-(naphthalen-1-yl)anthracen-9-yl]biphenyl, dibenzo{[f,f']-4,4',7,7'-tetraphenyl}diindeno[1,2,3 -Cd: 1',2',3'-lm]perylene, 1-(7-(9,9'-bianthracene-10-yl)-9,9-dimethyl-9H-fluoren-2-yl)pyrene , 1-(7-(9,9'-Bianthracen-10-yl)-9,9-dihexyl-9H -Fluoren-2-yl)pyrene, 1,3-bis(carbazol-9-yl)benzene, 1,3,5-tris(carbazol-9-yl)benzene, 4,4',4"-tris(carbazole -9-yl)triphenylamine, 4,4'-bis(carbazol-9-yl)biphenyl (CBP), 4,4'-bis(carbazol-9-yl)-2,2'-dimethylbiphenyl, 2 ,7-Bis(carbazol-9-yl)-9,9-dimethylfluorene, 2,2',7,7'-tetrakis(carbazol-9-yl)-9,9-spirobifluorene, 2,7- Bis(carbazol-9-yl)-9,9-di(p-tolyl)fluorene, 9,9-bis[4-(carbazol-9-yl)-phenyl]fluorene, 2,7-bis(carbazol-9) -Yl)-9,9-spirobifluorene, 1,4-bis(triphenylsilyl)benzene, 1,3-bis(triphenylsilyl)benzene, bis(4-N,N-diethylamino-2-methylphenyl )-4-Methylphenylmethane, 2,7-bis(carbazol-9-yl)-9,9-dioctylfluorene, 4,4"-di(triphenylsilyl)-p-terphenyl, 4,4'- Di(triphenylsilyl)biphenyl, 9-(4-t-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole, 9-(4-t-butylphenyl)-3,6-ditrityl -9H-carbazole, 9-(4-t-butylphenyl)-3,6-bis(9-(4-methoxyphenyl)-9H-fluoren-9-yl)-9H-carbazole, 2,6-bis( 3-(9H-carbazol-9-yl)phenyl)pyridine, triphenyl(4-(9-phenyl-9H-fluoren-9-yl)phenyl)silane, 9,9-dimethyl-N,N-diphenyl-7 -(4-(1-phenyl-1H-benzo[d]imidazol-2-yl)phenyl)-9H-fluoren-2-amine, 3,5-bis(3-(9H-carbazol-9-yl)phenyl ) Pyridine, 9,9-spirobifluoren-2-yl-diphenyl-phosphine oxide, 9,9'-(5-(triphenylsilyl)-1,3-phenylene)bis(9H-carbazole), 3-( 2,7-bis(diphenylphosphoryl)-9-phenyl-9H-fluoren-9-yl)-9-phenyl-9H-carbazole, 4,4,8,8 , 12,12-hexa(p-tolyl)-4H-8H-12H-12C-azadibenzo[cd,mn]pyrene, 4,7-di(9H-carbazol-9-yl)-1,10-phenanthroline, 2 ,2'-bis(4-(carbazol-9-yl)phenyl)biphenyl, 2,8-bis(diphenylphosphoryl)dibenzo[b,d]thiophene, bis(2-methylphenyl)diphenylsilane, bis[ 3,5-di(9H-carbazol-9-yl)phenyl]diphenylsilane, 3,6-bis(carbazol-9-yl)-9-(2-ethyl-hexyl)-9H-carbazole, 3-(diphenyl Phosphoryl)-9-(4-(diphenylphosphoryl)phenyl)-9H-carbazole, 3,6-bis[(3,5-diphenyl)phenyl]-9-phenylcarbazole, and the like, and light emitting property. The emissive layer may be formed by co-evaporating with a dopant.

As the luminescent dopant, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-10- (2-Benzothiazolyl)quinolidino[9,9a,1gh]coumarin, quinacridone, N,N'-dimethyl-quinacridone, tris(2-phenylpyridine)iridium(III)(Ir(ppy) ₃ ), bis(2-phenyl) Pyridine)(acetylacetonate)iridium(III)(Ir(ppy) ₂ (acac)), tris[2-(p-tolyl)pyridine]iridium(III)(Ir(mppy) ₃ ), 9,10-bis [N,N-di(p-tolyl)amino]anthracene, 9,10-bis[phenyl(m-tolyl)amino]anthracene, bis[2-(2-hydroxyphenyl)benzothiazolato]zinc(II), N ^{10 , N 10, N 10 ',} N 10' - tetra (p- tolyl) -9,9'-bi anthracene -10,10'- ^{diamine, N 10, N 10, N} 10 ', N 10' - tetraphenyl 9,9'-bi anthracene -10,10'- diamine, N ^10, N ^{10 '-} diphenyl -N ^10, N ^10' - Jinafutareniru 9,9'-bi anthracene -10,10'- diamine, 4 ,4′-bis(9-ethyl-3-carbazovinylene)-1,1′-biphenyl, perylene, 2,5,8,11-tetra-t-butylperylene, 1,4-bis[2-(3- N-ethylcarbazolyl)vinyl]benzene, 4,4′-bis[4-(di-p-tolylamino)styryl]biphenyl, 4-(di-p-tolylamino)-4′-[(di-p- Tolylamino)styryl]stilbene, bis[3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)]iridium(III),4,4′-bis[4-(diphenylamino)styryl] Biphenyl, bis(2,4-difluorophenylpyridinato)tetrakis(1-pyrazolyl)borateiridium(III), N,N'-bis(naphthalen-2-yl)-N,N'-bis(phenyl)- Tris(9,9-dimethylfluorenylene), 2,7-bis{2-[phenyl(m-tolyl)amino]-9,9-dimethyl-fluoren-7-yl}-9,9-dimethyl-fluorene , N-(4-((E)-2-(6(( E)-4-(diphenylamino)styryl)naphthalen-2-yl)vinyl)phenyl)-N-phenylbenzenamine, fac-iridium(III) tris(1-phenyl-3-methylbenzimidazoline-2-ylidene- C,C2 ^' ), mer-iridium(III) tris(1-phenyl-3-methylbenzimidazoline-2-ylidene-C,C2 ^' ), 2,7-bis[4-(diphenylamino)styryl] -9,9-spirobifluorene, 6-methyl-2-(4-(9-(4-(6-methylbenzo[d]thiazol-2-yl)phenyl)anthracen-10-yl)phenyl)benzo[d ] Thiazole, 1,4-di[4-(N,N-diphenyl)amino]styrylbenzene, 1,4-bis(4-(9H-carbazol-9-yl)styryl)benzene, (E)-6- (4-(diphenylamino)styryl)-N,N-diphenylnaphthalen-2-amine, bis(2,4-difluorophenylpyridinato)(5-(pyridin-2-yl)-1H-tetrazolate)iridium( III), bis(3-trifluoromethyl-5-(2-pyridyl)pyrazole)((2,4-difluorobenzyl)diphenylphosphinate)iridium(III), bis(3-trifluoromethyl-5-( 2-Pyridyl)pyrazolate)(benzyldiphenylphosphinate)iridium(III), bis(1-(2,4-difluorobenzyl)-3-methylbenzimidazolium)(3-(trifluoromethyl)-5-( 2-pyridyl)-1,2,4-triazolate)iridium(III), bis(3-trifluoromethyl-5-(2-pyridyl)pyrazolate)(4′,6′-difluorophenylpyridinate)iridium( III), bis(4',6'-difluorophenylpyridinato)(3,5-bis(trifluoromethyl)-2-(2'-pyridyl)pyrrolate)iridium(III), bis(4',6) '-Difluorophenylpyridinato)(3-(trifluoromethyl)-5-(2-pyridyl)-1,2,4-triazolate)iridium(III), (Z)-6-mesityl-N-(6 - mesityl quinolin -2 (IH) - ylidene) quinolin-2-amine _{-BF 2, (E) -2- (} 2- (4- ( dimethylamino) styryl) -6-methyl -4H- pyran-4 Ylidene) malononitrile, 4-(dissi Anomethylene)-2-methyl-6-jurolidyl-9-enyl-4H-pyran, 4-(dicyanomethylene)-2-methyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl )-4H-Pyran, 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran, tris(dibenzoyl) Methane)phenanthroline europium (III), 5,6,11,12-tetraphenylnaphthacene, bis(2-benzo[b]thiophen-2-yl-pyridine)(acetylacetonate)iridium (III), tris(1) -Phenylisoquinoline)iridium(III), bis(1-phenylisoquinoline)(acetylacetonate)iridium(III), bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline](acetyl Acetonate)iridium(III), bis[2-(9,9-dimethyl-9H-fluoren-2-yl)quinoline](acetylacetonate)iridium(III), tris[4,4′-di-t- Butyl-(2,2′)-bipyridine]ruthenium(III).bis(hexafluorophosphate), tris(2-phenylquinoline)iridium(III), bis(2-phenylquinoline)(acetylacetonate)iridium( III), 2,8-di-t-butyl-5,11-bis(4-t-butylphenyl)-6,12-diphenyltetracene, bis(2-phenylbenzothiazolate)(acetylacetonate)iridium (III), 5,10,15,20-tetraphenyltetrabenzoporphyrin platinum, osmium(II) bis(3-trifluoromethyl-5-(2-pyridine)-pyrazolate)dimethylphenylphosphine, osmium(II) Bis(3-(trifluoromethyl)-5-(4-t-butylpyridyl)-1,2,4-triazolate)diphenylmethylphosphine, osmium(II) bis(3-(trifluoromethyl)-5- (2-Pyridyl)-1,2,4-triazole)dimethylphenylphosphine, osmium(II)bis(3-(trifluoromethyl)-5-(4-t-butylpyridyl)-1,2,4- Triazolate)dimethylphenylphosphine, bis[2-(4-n-hexylphenyl)quinoline](acetylacetonate)iridium(II I), tris[2-(4-n-hexylphenyl)quinoline]iridium(III), tris[2-phenyl-4-methylquinoline]iridium(III), bis(2-phenylquinoline)(2-(3 -Methylphenyl)pyridinate)iridium(III), bis(2-(9,9-diethyl-fluoren-2-yl)-1-phenyl-1H-benzo[d]imidazolato)(acetylacetonate)iridium(III) , Bis(2-phenylpyridine)(3-(pyridin-2-yl)-2H-chromen-2-onate)iridium(III), bis(2-phenylquinoline)(2,2,6,6-tetramethyl Heptane-3,5-dionate)iridium(III), bis(phenylisoquinoline)(2,2,6,6-tetramethylheptane-3,5-dionate)iridium(III), iridium(III)bis(4-) Phenylthieno[3,2-c]pyridinato-N,C2 ^' )acetylacetonate, (E)-2-(2-t-butyl-6-(2-(2,6,6-trimethyl-2,2 4,5,6-Tetrahydro-1H-pyrrolo[3,2,1-ij]quinolin-8-yl)vinyl)-4H-pyran-4-ylidene)malononitrile, bis(3-trifluoromethyl-5-( 1-isoquinolyl)pyrazolate)(methyldiphenylphosphine)ruthenium, bis[(4-n-hexylphenyl)isoquinoline](acetylacetonate)iridium(III), platinum(II) octaethylporphine, bis(2-methyldibenzo) Examples include [f,h]quinoxaline)(acetylacetonate)iridium(III) and tris[(4-n-hexylphenyl)xoquinoline]iridium(III).

As a material for forming the electron transport layer, 8-hydroxyquinolinolate-lithium, 2,2′,2″-(1,3,5-benzintolyl)-tris(1-phenyl-1-H-benzimidazole) is used. ), 2-(4-biphenyl)5-(4-t-butylphenyl)-1,3,4-oxadiazole, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 4, 7-diphenyl-1,10-phenanthroline, bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminum, 1,3-bis[2-(2,2'-bipyridin-6-yl) -1,3,4-oxadiazo-5-yl]benzene, 6,6'-bis[5-(biphenyl-4-yl)-1,3,4-oxadiazo-2-yl]-2,2'- Bipyridine, 3-(4-biphenyl)-4-phenyl-5-t-butylphenyl-1,2,4-triazole, 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2 ,4-triazole, 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline, 2,7-bis[2-(2,2'-bipyridin-6-yl) -1,3,4-Oxadiazo-5-yl]-9,9-dimethylfluorene, 1,3-bis[2-(4-t-butylphenyl)-1,3,4-oxadiazo-5-yl] Benzene, tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane, 1-methyl-2-(4-(naphthalen-2-yl)phenyl)-1H-imidazo[4. 5f][1,10]phenanthroline, 2-(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline, phenyl-dipyrenylphosphine oxide, 3,3′,5,5′- Tetra[(m-pyridyl)-phen-3-yl]biphenyl, 1,3,5-tris[(3-pyridyl)-phen-3-yl]benzene, 4,4'-bis(4,6-diphenyl) -1,3,5-triazin-2-yl)biphenyl, 1,3-bis[3,5-di(pyridin-3-yl)phenyl]benzene, bis(10-hydroxybenzo[h]quinolinato)beryllium, Examples thereof include diphenylbis(4-(pyridin-3-yl)phenyl)silane and 3,5-di(pyren-1-yl)pyridine.

Materials for forming the electron injection layer include lithium oxide (Li ₂ O), magnesium oxide (MgO), alumina (Al ₂ O ₃ ), lithium fluoride (LiF), sodium fluoride (NaF), magnesium fluoride ( MgF ₂ ), cesium fluoride (CsF), strontium fluoride (SrF ₂ ), molybdenum trioxide (MoO ₃ ), aluminum, Li(acac), lithium acetate, lithium benzoate and the like.
Examples of the cathode material include aluminum, magnesium-silver alloy, aluminum-lithium alloy, lithium, sodium, potassium and cesium.

Further, another example of the method for producing an organic EL device having a hole injection layer formed of a thin film obtained from the charge transporting varnish of the present invention is as follows.
In the above EL device preparation, instead of performing the vacuum deposition operation of the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, a hole transport layer (hereinafter, hole transporting polymer layer), a light emitting layer (hereinafter, By sequentially forming the light-emitting polymer layer), an organic EL device having a charge-transporting thin film formed by the charge-transporting varnish of the present invention can be prepared.
Specifically, the charge transporting varnish of the present invention is applied onto an anode substrate to prepare a hole injecting layer by the above method, and a hole transporting polymer layer and a light emitting polymer layer are sequentially formed thereon. After formation, a cathode electrode is vapor-deposited to obtain an organic EL device.

As the cathode and anode materials used, the same materials as those described above can be used, and the same cleaning treatment and surface treatment can be performed.
The hole transporting polymer layer and the light emitting polymer layer can be formed by adding a solvent to the hole transporting polymer material or the light emitting polymer material, or a material obtained by adding a dopant substance to the material and dissolving it. A method of forming a film by uniformly dispersing, coating on the hole injecting layer or the hole transporting polymer layer, and then firing each is described.

Examples of the hole transporting polymer material include poly[(9,9-dihexylfluorenyl-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1,4-diamino). Phenylene)], poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1,1'-biphenylene-4,4- Diamine)], poly[(9,9-bis{1'-penten-5'-yl}fluorenyl-2,7-diyl)-co-(N,N'-bis{p-butylphenyl}-1, 4-diaminophenylene)], poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)-benzidine]-endcapped with polysilcisquinoxane, poly[(9,9 -Didioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(p-butylphenyl))diphenylamine)] and the like.

Examples of the light emitting polymer material include poly(9,9-dialkylfluorene) (PDAF) and other polyfluorene derivatives, poly(2-methoxy-5-(2'-ethylhexoxy)-1,4-phenylenevinylene) (MEH). -PPV) and other polyphenylene vinylene derivatives, poly(3-alkylthiophene) (PAT) and other polythiophene derivatives, and polyvinylcarbazole (PVCz).

Examples of the solvent include toluene, xylene, chloroform and the like, and examples of the dissolution or uniform dispersion method include stirring, heating stirring, ultrasonic dispersion and the like.
The coating method is not particularly limited, and examples thereof include an inkjet method, a spray method, a dip method, a spin coating method, a transfer printing method, a roll coating method, and a brush coating method. The coating is preferably performed under an inert gas such as nitrogen or argon.
Examples of the baking method include a method of heating in an oven or a hot plate under an inert gas or in vacuum.

An example of a method for producing an EL device having a hole transport layer composed of a thin film obtained from the charge transport varnish of the present invention is as follows.
A hole injection layer is formed on the anode substrate. The charge-transporting varnish of the present invention is applied onto the layer by the above-mentioned method and baked to form a hole-transporting layer.
On this hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a cathode are provided in this order. The methods and specific examples of forming the light emitting layer, the electron transporting layer and the electron injecting layer are the same as those described above. In addition, the hole injection layer may be formed by either an evaporation method or a coating method (wet process) depending on characteristics of a material used or the like.

As a material for forming the hole injection layer, copper phthalocyanine, titanium oxide phthalocyanine, platinum phthalocyanine, pyrazino[2,3-f][1,10]phenanthroline-2,3-dicarbonitrile, N,N,N'. , N'-tetrakis(4-methoxyphenyl)benzidine, 2,7-bis[N,N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, 2,2'-bis[N , N-bis(4-methoxy-phenyl)amino]-9,9-spirobifluorene, N,N'-diphenyl-N,N'-di[4-(N,N-ditolylamino)phenyl]benzidine, N , N'- diphenyl -N, N'- di [4- (N, N- diphenylamino) phenyl] ^{benzidine, N 4, N 4 '-} ( biphenyl-4,4'-diyl) bis (N ^4, N ^{4 ',} N ^4' - ^{triphenyl-biphenyl-4,4'-diamine) N 1, N 1 '-} ( biphenyl-4,4'-diyl) bis (N ¹ - phenyl -N ^4, N ^4' - di -M-tolylbenzene-1,4-diamine), International Publication No. 2004/043117, International Publication No. 2004/105446, International Publication No. 2005/000832, International Publication No. 2005/043962, International Publication No. 2005/ 042621, International Publication No. 2005/107335, International Publication No. 2006/006459, International Publication No. 2006/025342, International Publication No. 2006/137473, International Publication No. 2007/049631, International Publication No. 2007/099808. , International Publication No. 2008/010474, International Publication No. 2008/032617, International Publication No. 2008/032616, International Publication No. 2008/129947, International Publication No. 2009/096352, International Publication No. 2010/041701, International Publication No. 2010/058777, International Publication No. 2010/058776, International Publication No. 2013/042623, International Publication No. 2013/129249, International Publication No. 2014/115865, International Publication No. 2014/132917, International Publication No. The charge transport materials described in 2014/141998 and International Publication 2014/132834 can be mentioned.

As the anode material, the light emitting layer, the light emitting dopant, the material forming the electron transport layer and the electron blocking layer, and the cathode material, the same ones as described above can be mentioned.

An example of a method for producing an organic EL device having a hole injecting and transporting layer composed of a thin film obtained from the charge transporting varnish of the present invention is as follows.
A hole injecting and transporting layer is formed on the anode substrate, and a light emitting layer, an electron transporting layer, an electron injecting layer, and a cathode are provided in this order on the hole injecting and transporting layer. The methods and specific examples of forming the light emitting layer, the electron transporting layer and the electron injecting layer are the same as those described above.

As the anode material, the light emitting layer, the light emitting dopant, the material forming the electron transport layer and the electron blocking layer, and the cathode material, the same ones as described above can be mentioned.

Note that a hole block layer, an electron block layer, or the like may be provided between the electrodes and any of the above layers, if necessary. For example, as a material for forming the electron block layer, tris(phenylpyrazole)iridium or the like can be given.

The materials forming the anode and the cathode and the layers formed between them differ depending on whether the element having the bottom mission structure or the top emission structure is manufactured. Therefore, the material is appropriately selected in consideration of this point.
Normally, in a bottom emission structure element, a transparent anode is used on the substrate side, and light is extracted from the substrate side, whereas in a top emission structure element, a reflective anode made of metal is used, and the light is extracted in the opposite direction to the substrate. Since light is extracted from a certain transparent electrode (cathode) side, for example, regarding an anode material, a transparent anode such as ITO is manufactured when manufacturing a device having a bottom emission structure, and Al is manufactured when manufacturing a device having a top emission structure. A reflective anode such as /Nd is used.

The organic EL device of the present invention may be sealed with a water catching agent and the like according to a conventional method in order to prevent deterioration of characteristics.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. The equipment used is as follows.
(1) ¹ H, ¹⁹ F-NMR: JEOL's nuclear magnetic resonance apparatus AL-300
(2) Substrate cleaning: Choshu Sangyo Co., Ltd. substrate cleaning equipment (depressurized plasma method)
(3) Application of varnish: Spin coater MS-A100 manufactured by Mikasa Co., Ltd.
(4) Film thickness measurement: manufactured by Kosaka Laboratory Co., Ltd. Fine shape measuring instrument Surfcoder ET-4000
(5) Surface observation of film: Confocal laser microscope manufactured by Lasertec Co., Ltd. Real-time scanning laser microscope 1LM21D
(6) Manufacture of EL element: Multi-functional vapor deposition system C-E2L1G1-N manufactured by Choshu Sangyo Co., Ltd.
(7) Measurement of brightness of EL element: (Present) Tech World I-V-L measurement system (8) Life measurement of EL element (measurement of brightness half-life): Organic EL brightness manufactured by ETC Life evaluation system PEL-105S

[1] Synthesis of onium borate salt [Synthesis example 1] Synthesis of (4-phenylthiophenyl)diphenylsulfonium n-butyl tris(pentafluorophenyl)borate salt

38.1 parts by mass of tris(pentafluorophenyl)borane (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1200 parts by mass of pentane were charged into a reaction vessel, and a hexane solution of n-butyllithium (1.6M) was stirred at room temperature. 38.8 parts by mass was dropped, and the mixture was reacted at room temperature for 3 hours to obtain a slurry-like reaction liquid.
The crystalline product obtained by filtering the reaction solution was spray washed with pentane and dried under reduced pressure at 60° C. to obtain 38.1 parts by mass of lithium n-butyl tris(pentafluorophenyl)borate as an intermediate (collection). Rate 89%).

Subsequently, 30 parts by mass of the borate obtained above was added to a solution prepared by dissolving 22.5 parts by mass of (4-phenylthiophenyl)diphenylsulfonium hexafluorophosphate (manufactured by San-Apro Ltd.) in 530 parts by mass of dichloromethane. An aqueous solution dissolved in 400 parts by mass of exchanged water was added and mixed for 1 hour with stirring. After mixing, the mixture was allowed to stand to remove the aqueous layer, and the dichloromethane solution was washed 5 times with 400 parts by mass of ion-exchanged water. The dichloromethane solution after washing with water was desolvated under reduced pressure to obtain 40 parts by mass of a pale yellow solid of (4-phenylthiophenyl)diphenylsulfonium n-butyl tris(pentafluorophenyl)borate salt, which is a target substance (yield 97 %). The obtained target product was identified by ¹ H-NMR and ¹⁹ F-NMR.
¹ H-NMR (DMSO-d6): δ 7.6 to 7.8 (12H, m), 7.4 to 7.5 (5H, m), 7.3 (2H, d), 1.0 to. 1.2 (4H, m), 0.6-0.8 (5H, m) ppm.
¹⁹ F-NMR (DMSO-d6): δ-132 (6F, d), -159.5 (3F, t), -163 (6F, t) ppm.

[2] Preparation of charge-transporting varnish [Example 1-1]
158 mg of PCZ5 represented by the following formula synthesized according to the method described in Production Example 18 of WO 2015/050253 and (4-phenylthiophenyl)diphenylsulfonium n-butyl tris(pentafluorophenyl) obtained in Synthesis Example 1 To a mixture with 105 mg of borate salt, 5 g of xylene was added and dissolved by stirring while irradiating ultrasonic waves at room temperature, and the resulting solution was filtered with a syringe filter having a pore size of 0.2 μm to obtain a charge-transporting varnish. Obtained.

[3] Preparation of organic EL device and characteristic evaluation [Example 2-1]
The varnish obtained in Example 1-1 was applied to an ITO substrate using a spin coater, dried at 80° C. for 1 minute, and further baked at 150° C. for 10 minutes in the air atmosphere to form an ITO substrate. A 100 nm uniform thin film was formed. As the ITO substrate, a glass substrate of 25 mm×25 mm×0.7 t in which indium tin oxide (ITO) was patterned on the surface with a film thickness of 150 nm was used, and an O ₂ plasma cleaning device (150 W, 30 seconds) was used before use. To remove impurities on the surface.
Then, α-NPD(N,N′-di(1-naphthyl)-N,N′-diphenyl was formed on the ITO substrate on which the thin film was formed by using a vapor deposition apparatus (vacuum degree 1.0×10 ⁻⁵ Pa). Benzidine) was formed into a 30 nm film at 0.2 nm/sec. Next, CBP and Ir(PPy) ₃ were co-evaporated. The co-evaporation was performed by controlling the vapor deposition rate so that the Ir(PPy) ₃ concentration was 6%, and stacking 40 nm. Then, thin films of BAlq, lithium fluoride and aluminum were sequentially laminated to obtain an organic EL element. At this time, the vapor deposition rate was 0.2 nm/sec for BAlq and aluminum, and 0.02 nm/sec for lithium fluoride, and the film thickness was 20 nm, 0.5 nm, and 120 nm, respectively.
In order to prevent characteristic deterioration due to the influence of oxygen, water, etc. in the air, the organic EL element was sealed with a sealing substrate and then the characteristics were evaluated. The sealing was performed by the following procedure. In a nitrogen atmosphere having an oxygen concentration of 2 ppm or less and a dew point of −85° C. or less, the organic EL element is housed between sealing substrates, and the sealing substrates are bonded with an adhesive (XNR5516Z-B1 manufactured by Nagase Chemtex Co., Ltd.). It was At this time, a water catching agent (HD-071010W-40, manufactured by Dynic Co., Ltd.) was put in the sealing substrate together with the organic EL element. The bonded sealing substrates were irradiated with UV light (wavelength: 365 nm, irradiation amount: 6,000 mJ/cm ² ) and then annealed at 80° C. for 1 hour to cure the adhesive.

For the device of Example 2-1, the driving voltage, current density, and luminous efficiency when driven at a luminance of 5000 cd/m ² and the half-life of the luminance (the time required for the initial luminance of 5000 cd/m ² to reach half) were obtained. It was measured. The results are shown in Table 19.

As shown in Table 19, the EL device including the charge transporting thin film of the present invention was favorably driven. It also had excellent life characteristics.

Claims (6)

Including a charge-transporting substance, an onium borate salt, and an organic solvent,
A charge-transporting varnish characterized in that the onium borate salt contains an onium borate salt consisting of an anion represented by formula (a1) and a counter cation.

(In the formula, R represents an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or a fluoroaralkyl group having 7 to 10 carbon atoms.) The charge-transporting varnish according to claim 1, wherein the charge-transporting substance is at least one selected from aniline derivatives and thiophene derivatives. The charge-transporting varnish according to claim 2, wherein the charge-transporting substance is an aniline derivative. A charge-transporting thin film produced by using the charge-transporting varnish according to claim 1. An organic electroluminescence device comprising the charge transporting thin film according to claim 4. A method for producing a charge-transporting thin film, comprising applying the charge-transporting varnish according to any one of claims 1 to 3 onto a substrate and evaporating the solvent.